OAKLAND (AP) — Construction has begun on the Bay Area Rapid Transit's extension to Oakland International Airport despite criticism of the project's $500 million price tag and potential to create jobs.The concrete columns that will support the 3.2-mile connector's elevated track have started going up, the Oakland Tribune reported Tuesday. The cable-drawn train system is expected to be completed by 2014.But critics, including a BART board member, say the extension is unnecessary and is going forward at the expense of more important BART projects. The cost has risen from an initial projection of $130 million. The job projections, meanwhile, have dropped from 13,000 to about 2,500.The project also ran into opposition from the Federal Transit Administration, which denied BART $70 million in funding last year on the grounds that the agency could not meet deadlines for a required study of the project's impact on minority residents."With the earlier BART administration, there were a lot of promises made that are not being met, and there is no way they will be," Robert Raburn, a BART board member, told the Tribune.Raburn tried to kill the connector project after he was elected in 2010. "I came along just a little bit too late in the process to have that kind of impact, so my goal now is to live with it and make sure we get the deliverables promised," he said.The extension project was proposed more than a decade ago and then dropped and picked up over the years.BART officials say the initial cost estimate was not accurate. They blamed delays and a souring economy for the current $500 million estimate and say the train will be faster and more reliable than the current bus system connecting BART to the airport."Generations from now, people will wonder why there was any debate about (this project)," said BART spokesman Jim Allison.BART has said it would have to charge $12 roundtrip to cover the cost of the connector project. The bus currently costs $6 round trip. But Allison said the BART board could decide to lower the fare and subsidize the airport connector project through other revenues.